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Please provide information about your system and the version of Clementine used.

I had the same issue after upgrading to 10.14. As a workaround, I enabled clementine.app in 'Allow the apps below to control your computer' in the accessibility section of security and privacy, which allowed clementine to launch normally.
see attached

It works. Thank you
These things will keep happening if we don't get a new version of the app in years ....
No this is a prevalent problem for a bunch of different apps on Mojave. Mojave changed how security payloads work this isn't just Clementine. This is a duplicate of #6148.
@jrkong I think I wasn't clear enough. I am not talking about this precise Mojave thing. I am talking that since we don't have a release in two years, the latest stable binary will be more likely to be less compatible with newer versions of any OS day by day ...
Clementine 1.3.1 was release on Apr 2016, if we are talking just about Apple, then we have Sierra September 2016, High Sierra September 2017 and now Mojave September 2018. I was just pure luck that we didn't get any breaking change for 2 years and a half ...
can you see the problem ?
BTW, @dynched's "fix"
I had the same issue after upgrading to 10.14. As a workaround, I enabled clementine.app in 'Allow the apps below to control your computer' in the accessibility section of security and privacy, which allowed clementine to launch normally.
works, but you might have to insist. Clementine 1st opened the Preference window, the checkmark was checked, and yet it crashed. I had to do these steps for it to settle, after many crashes:
and then it took.
p.s. Clarification:
Clementine (unknown version) was installed, then I upgraded to Mojave, then the crashes happen, so I couldn't check the actual version I had.
After I downloaded and installed the latest, MAYBE Clementine was still crashing because of this Accessibility checkmark because it was not actually the same app (I'm spitballing here). Once the new app was installed, I unchecked, then rechecked the checkmark, which possibly registered the right app (latest download). Dunno... Anyway, it's OK now.
Fixed by #6210. It's not in a release but it's fixed and merged.
Thanks, it worked for me
Most helpful comment
I had the same issue after upgrading to 10.14. As a workaround, I enabled clementine.app in 'Allow the apps below to control your computer' in the accessibility section of security and privacy, which allowed clementine to launch normally.
see attached